Network


Latest external collaboration on country level. Dive into details by clicking on the dots.

Hotspot


Dive into the research topics where Peter J. Kahrilas is active.

Publication


Featured researches published by Peter J. Kahrilas.


The American Journal of Gastroenterology | 2006

The Montreal definition and classification of gastroesophageal reflux disease: a global evidence-based consensus.

Nimish Vakil; Sander Veldhuyzen van Zanten; Peter J. Kahrilas; John Dent; Roger Jones

OBJECTIVES:A globally acceptable definition and classification of gastroesophageal reflux disease (GERD) is desirable for research and clinical practice. The aim of this initiative was to develop a consensus definition and classification that would be useful for patients, physicians, and regulatory agencies.METHODS:A modified Delphi process was employed to reach consensus using repeated iterative voting. A series of statements was developed by a working group of five experts after a systematic review of the literature in three databases (Embase, Cochrane trials register, Medline). Over a period of 2 yr, the statements were developed, modified, and approved through four rounds of voting. The voting group consisted of 44 experts from 18 countries. The final vote was conducted on a 6-point scale and consensus was defined a priori as agreement by two-thirds of the participants.RESULTS:The level of agreement strengthened throughout the process with two-thirds of the participants agreeing with 86%, 88%, 94%, and 100% of statements at each vote, respectively. At the final vote, 94% of the final 51 statements were approved by 90% of the Consensus Group, and 90% of statements were accepted with strong agreement or minor reservation. GERD was defined as a condition that develops when the reflux of stomach contents causes troublesome symptoms and/or complications. The disease was subclassified into esophageal and extraesophageal syndromes. Novel aspects of the new definition include a patient-centered approach that is independent of endoscopic findings, subclassification of the disease into discrete syndromes, and the recognition of laryngitis, cough, asthma, and dental erosions as possible GERD syndromes. It also proposes a new definition for suspected and proven Barretts esophagus.CONCLUSIONS:Evidence-based global consensus definitions are possible despite differences in terminology and language, prevalence, and manifestations of the disease in different countries. A global consensus definition for GERD may simplify disease management, allow collaborative research, and make studies more generalizable, assisting patients, physicians, and regulatory agencies.


Gut | 1999

An evidence-based appraisal of reflux disease management - The Genval Workshop Report

J. Brun; A. M. Fendrick; M. B. Fennerty; Jozef Janssens; Peter J. Kahrilas; K. Lauritsen; J. C. Reynolds; M. Shaw; Nicholas J. Talley

This report summarises conclusions from an evidence-based workshop which evaluated major clinical strategies for the management of the full spectrum of gastro-oesophageal reflux disease, with an emphasis on medical management. The disease was defined by the presence of oesophageal mucosal breaks or by the occurrence of reflux induced symptoms severe enough to impair quality of life. Endoscopy negative patients were recognised as the most common subgroup; most of these patients can be diagnosed by a well structured symptom analysis. There is a consistent hierarchy of effectiveness of available initial and long term therapies that applies for all patient subgroups. Lifestyle measures were judged to be of such low efficacy that they were rejected as a primary therapy for all patient subgroups. Proton pump inhibitor therapy was considered the initial medical treatment of choice because of its clearly superior efficacy which results in the most prompt achievement of desirable outcomes at the lowest overall medical cost. It was acknowledged that most of patients require long term management and that any maintenance therapy should be chosen by step down to the regimen that is still effective, but least costly. Endoscopic monitoring of routine long term therapy was considered inappropriate, on the basis that control of symptoms is an acceptably reliable indicator of healing in patients with oesophagitis. Laparoscopic antireflux surgery was recognised as a significant therapeutic advance, the results of which, however, depend substantially on the experience of the surgeon. There are currently no published direct comparisons of cost and efficacy outcomes of optimal medical and surgical therapies for reflux disease. To a significant degree, the choice between medical and surgical therapy should depend on informed patient preference. Substantial advances have occurred recently in the understanding and treatment of reflux disease. By contrast, there has been relatively little research into the best …


Gastroenterology | 1986

Esophageal Peristaltic Dysfunction in Peptic Esophagitis

Peter J. Kahrilas; Wylie J. Dodds; Walter J. Hogan; Mark Kern; Ronald C. Arndorfer; A. Reece

Esophageal exposure to acid is a major determinant in the pathogenesis of reflux esophagitis. In this study, we analyzed the esophageal peristaltic function of 177 patients and asymptomatic volunteers for abnormalities that could lead to prolonged esophageal acid clearance. The subjects were divided into five groups: normal volunteers, patient controls, patients with noninflammatory gastroesophageal reflux disease, patients with mild esophagitis, and ones with severe esophagitis. Manometric data were analyzed for the occurrence of failed primary peristalsis, for the occurrence of feeble peristalsis in the distal esophagus, and for hypotensive lower esophageal sphincter pressure. From an analysis of the data on control patients, peristaltic dysfunction was defined as the occurrence of either failed primary peristalsis or hypotensive peristalsis in the distal esophagus for over half of the test swallows. Peristaltic dysfunction was increasingly prevalent with increasing severity of peptic esophagitis, occurring in 25% of patients with mild esophagitis and 48% of patients with severe esophagitis. A correlation did not exist between the occurrence of peristaltic dysfunction and hypotensive lower esophageal sphincter pressure (less than or equal to 10 mmHg). We conclude that peristaltic dysfunction occurs in a substantial minority of patients with peptic esophagitis and could contribute to increased esophageal exposure to refluxed acid material.


Neurogastroenterology and Motility | 2012

Chicago classification criteria of esophageal motility disorders defined in high resolution esophageal pressure topography.

Albert J. Bredenoord; Mark Fox; Peter J. Kahrilas; John E. Pandolfino; Werner Schwizer; Andreas J. Smout

Background  The Chicago Classification of esophageal motility was developed to facilitate the interpretation of clinical high resolution esophageal pressure topography (EPT) studies, concurrent with the widespread adoption of this technology into clinical practice. The Chicago Classification has been an evolutionary process, molded first by published evidence pertinent to the clinical interpretation of high resolution manometry (HRM) studies and secondarily by group experience when suitable evidence is lacking.


Gastroenterology | 2008

Achalasia: A New Clinically Relevant Classification by High-Resolution Manometry

John E. Pandolfino; Monika A. Kwiatek; Thomas B. Nealis; William J. Bulsiewicz; Jennifer Post; Peter J. Kahrilas

BACKGROUND & AIMS Although the diagnosis of achalasia hinges on demonstrating impaired esophagogastric junction (EGJ) relaxation and aperistalsis, 3 distinct patterns of aperistalsis are discernable with high-resolution manometry (HRM). This study aimed to compare the clinical characteristics and treatment response of these 3 subtypes. METHODS One thousand clinical HRM studies were reviewed, and 213 patients with impaired EGJ relaxation were identified. These were categorized into 4 groups: achalasia with minimal esophageal pressurization (type I, classic), achalasia with esophageal compression (type II), achalasia with spasm (type III), and functional obstruction with some preserved peristalsis. Clinical and manometric variables including treatment response were compared among the 3 achalasia subtypes. Logistic regression analysis was performed using treatment success as the dichotomous dependent variable controlling for independent manometric and clinical variables. RESULTS Ninety-nine patients were newly diagnosed with achalasia (21 type I, 49 type II, 29 type III), and 83 of these had sufficient follow-up to analyze treatment response. Type II patients were significantly more likely to respond to any therapy (BoTox [71%], pneumatic dilation [91%], or Heller myotomy [100%]) than type I (56% overall) or type III (29% overall) patients. Logistic regression analysis found type II to be a predictor of positive treatment response, whereas type III and pretreatment esophageal dilatation were predictive of negative treatment response. CONCLUSIONS Achalasia can be categorized into 3 subtypes that are distinct in terms of their responsiveness to medical or surgical therapies. Utilizing these subclassifications would likely strengthen future prospective studies of treatment efficacy in achalasia.


Neurogastroenterology and Motility | 2015

The Chicago Classification of esophageal motility disorders, v3.0

Peter J. Kahrilas; A. J. Bredenoord; M. R. Fox; C. P. Gyawali; Sabine Roman; A. J. P. M. Smout; John E. Pandolfino

The Chicago Classification (CC) of esophageal motility disorders, utilizing an algorithmic scheme to analyze clinical high‐resolution manometry (HRM) studies, has gained acceptance worldwide.


Gastroenterology | 1988

Effect of peristaltic dysfunction on esophageal volume clearance

Peter J. Kahrilas; Wylie J. Dodds; Walter J. Hogan

Prolonged esophageal acid clearance, found in some patients with esophagitis, can be attributed in part to the peristaltic dysfunction observed in this population. In this study, we undertook to define the effect of commonly observed peristaltic dysfunction on volume clearance by obtaining concurrent videofluoroscopic and manometric recordings in patients with nonobstructive dysphagia or heartburn. Excellent correlation existed between the findings from the two studies. A single normal peristaltic wave resulted in 100% clearance of a barium bolus from the esophagus. At each recording site, luminal closure, as demonstrated by videofluoroscopy, coincided with the upstroke of the peristaltic pressure complex. Absent or incomplete peristaltic contractions invariably resulted in little or no volume clearance from the involved segment. Regional hypotensive peristalsis was associated with incomplete volume clearance by the mechanism of retrograde escape of barium through the region of hypotensive contraction. The regional peristaltic amplitude required to prevent retrograde escape of barium was greater in the distal compared with the proximal esophagus. The mean peristaltic amplitude associated with instances of retrograde escape was 25 mmHg in the distal esophagus compared with 12 mmHg in the proximal esophageal segments. Thus, the peristaltic dysfunction commonly seen in patients with esophagitis (failed and hypotensive peristalsis) likely leads to impaired volume clearance.


Gastroenterology | 2008

American Gastroenterological Association Medical Position Statement on the management of gastroesophageal reflux disease.

Peter J. Kahrilas; Nicholas J. Shaheen; Michael F. Vaezi

The American Gastroenterological Association (AGA) Institute Medical Position Panel consisted of the authors of the technical review, a community-based gastroenterologist (Stephen W. Hiltz, MD, MBA, AGAF), an insurance provider representative (Edgar Black, MD, Medical Director, Policy Resources Technology Evaluation Center, BlueCross BlueShield Association), a general surgeon (Irvin M. Modlin, MD), a patient advocate (Gregory Lane), a primary care physician (Steve P. Johnson, MD), a gastroenterologist with expertise in health services research (Philip S. Schoenfeld, MD), the Chair of the AGA Institute Clinical Practice and Quality Management Committee (John Allen, MD, MBA, AGAF), and the Chair of the AGA Institute Practice Management and Economics Committee and the AGA Institute CPT Advisor (Joel V. Brill, MD, AGAF).


The American Journal of Gastroenterology | 2003

Ambulatory esophageal pH monitoring using a wireless system

John E. Pandolfino; Joel E. Richter; Tina M. Ours; Jason M. Guardino; Jennifer Chapman; Peter J. Kahrilas

OBJECTIVES:Limitations of catheter-based esophageal pH monitoring are discomfort, inconvenience, and interference with normal activity. An alternative to conventional pH monitoring is the wireless Medtronic Bravo pH System. The aim of this study was to evaluate the safety, performance, and tolerability of this system.METHODS:A total of 44 healthy subjects and 41 patients with gastroesophageal reflux disease (GERD) were studied for a 2-day period. The pH telemetry capsule was positioned transorally 6 cm above the squamocolumnar junction using endoscopic measurement. The signal transmitted from the capsule was received and recorded by a small, pager-sized receiver, and pH data were subsequently uploaded to a computer for analysis.RESULTS:Successful 24-h pH studies were completed in 82 subjects (96%). During the 24-h study period the median percentage of the time that pH was <4 was 2.3% (95th percentile, 5.9%) in controls and 6.5% (range, 0.8–27.6) in GERD patients. In 76 subjects (89%), 36–48 h recordings were obtained. For the extended period the median percentage of the time that pH was <40 was 2.0% (95% percentile, 5.3%) in controls and 6.6% (range, 1.0–26.7) in GERD patients. Capsules required endoscopic removal in three subjects (4%). Optimal sensitivity in distinguishing controls from reflux patients was achieved when analyzed from the perspective of the worst of the 2 days.CONCLUSION:The wireless Bravo pH System successfully recorded esophageal acid exposure in 96% of the patients during a 24-h period and in 89% of subjects for >36 h. The 95th percentile for the 2-day recordings in control subjects was 5.3%, slightly higher than observed with conventional systems.


The American Journal of Gastroenterology | 2002

Esomeprazole (40 mg) compared with lansoprazole (30 mg) in the treatment of erosive esophagitis

Donald O. Castell; Peter J. Kahrilas; Joel E. Richter; Nimish Vakil; David A. Johnson; Seth Zuckerman; Wendy Skammer; Jeffrey G. Levine

OBJECTIVES: Esomeprazole, the S isomer of omeprazole, has been shown to have higher healing rates of erosive esophagitis than omeprazole. This study compared esomeprazole with lansoprazole for the healing of erosive esophagitis and resolution of heartburn.METHODS:This United States multicenter, randomized, double blind, parallel group trial was performed in 5241 adult patients (intent-to-treat population) with endoscopically documented erosive esophagitis, which was graded by severity at baseline (Los Angeles classification). Patients received 40 mg of esomeprazole (n = 2624) or 30 mg of lansoprazole (n = 2617) once daily before breakfast for up to 8 wk. The primary efficacy endpoint was healing of erosive esophagitis at week 8. Secondary assessments included proportion of patients healed at week 4, resolution of investigator-recorded heartburn, time to first and time to sustained resolution of patient diary-recorded heartburn, and proportion of heartburn-free days and nights.RESULTS:Esomeprazole (40 mg) demonstrated significantly higher healing rates (92.6%, 95% CI = 91.5–93.6%) than lansoprazole (30 mg) (88.8%, 95% CI = 87.5–90.0%) at week 8 (p = 0.0001, life-table estimates, intent-to-treat analysis). A significant difference in healing rates favoring esomeprazole was also observed at week 4. The difference in healing rates between esomeprazole and lansoprazole increased as baseline severity of erosive esophagitis increased. Sustained resolution of heartburn occurred faster and in more patients treated with esomeprazole. Sustained resolution of nocturnal heartburn also occurred faster with esomeprazole. Both treatments were well tolerated.CONCLUSIONS:Esomeprazole (40 mg) is more effective than lansoprazole (30 mg) in healing erosive esophagitis and resolving heartburn. Healing rates are consistently high with esomeprazole, irrespective of baseline disease severity.

Collaboration


Dive into the Peter J. Kahrilas's collaboration.

Top Co-Authors

Avatar
Top Co-Authors

Avatar

Zhiyue Lin

Northwestern University

View shared research outputs
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar

Ikuo Hirano

Northwestern University

View shared research outputs
Top Co-Authors

Avatar
Top Co-Authors

Avatar

Sudip K. Ghosh

Pennsylvania State University

View shared research outputs
Top Co-Authors

Avatar

Guoxiang Shi

Northwestern University

View shared research outputs
Top Co-Authors

Avatar
Researchain Logo
Decentralizing Knowledge